Selam! I am a Ph.D. candidate at Princeton University in the Department of Electrical Engineering. My research interests are primarily in quantum computation and condensed matter physics. For graduate work, I have focused on electron spin resonance experiments on donor spins in silicon and electrons floating on superfluid helium as a member of Lyon lab.

Beyond research, I have worked on projects involving cryptography and reversible computing. More recently, I have been interested in blockchains and cryptocurrency markets.

We describe sensitive magnetometry using lumped-element resonators fabricated from a superconducting thin film of
NbTiN. Taking advantage of the large kinetic inductance of the superconductor, we demonstrate a continuous
resonance frequency shift of 27 MHz for a change in magnetic field of \(1.8~\mu\)T within a perpendicular background
field of 60 mT. By using phase-sensitive readout of microwaves transmitted through the sensors, we measure phase
shifts in real time with a sensitivity of 1 degree/nT. We present measurements of the noise spectral density of
the sensors, and find their field sensitivity is at least within one to two orders of magnitude of superconducting
quantum interference devices operating with zero background field. Our superconducting kinetic inductance
field-frequency sensors enable real-time magnetometry in the presence of moderate perpendicular background fields up
to at least 0.2 T. Applications for our sensors include the stabilization of magnetic fields in long coherence
electron spin resonance measurements and quantum computation.

We report transport measurements of electrons on helium in a microchannel device where the channels are 200 nm
deep and \(3~\mu\)m wide. The channels are fabricated above amorphous metallic Ta\(_{40}\)W\(_{40}\)Si\(_{20}\), which has surface roughness
below 1 nm and minimal variations in work function across the surface due to the absence of polycrystalline grains. We
are able to set the electron density in the channels using a ground plane. We estimate a mobility
of 300 cm\(^2\)/V\(\cdot\)s and electron densities as high as 2.56\(\times10^{9}\text{ cm}^{-2}\). We demonstrate control of the transport
using a barrier which enables pinchoff at a central microchannel connecting two reservoirs. The conductance
through the central microchannel is measured to be 10 nS for an electron density of 1.58\(\times10^{9}\text{ cm}^{-2}\). Our work
extends transport measurements of surface electrons to thin helium films in microchannel devices above metallic substrates.

Disordered superconducting materials provide a new capability to implement novel circuit designs due to their high kinetic inductance. Here, we realize a fluxonium qubit in which a long NbTiN nanowire shunts a single Josephson junction. We explain the measured fluxonium energy spectrum with a nonperturbative theory accounting for the multimode structure of the device in a large frequency range. Making use of multiphoton Raman spectroscopy, we address forbidden fluxonium transitions and observe multilevel Autler-Townes splitting. Finally, we measure lifetimes of several excited states ranging from \(T_1=620\) ns to \(T_1=20~\mu\)s, by applying consecutive \(\pi\)-pulses between multiple fluxonium levels. Our measurements demonstrate that NbTiN is a suitable material for novel superconducting qubit designs.

In this work, we demonstrate the use of frequency-tunable superconducting NbTiN coplanar waveguide microresonators
for multi-frequency pulsed electron spin resonance (ESR) experiments. By applying a bias current to the center pin,
the resonance frequency (\(\sim\)7.6 GHz) can be continuously tuned by as much as 95 MHz in 270 ns without a change in
the quality factor of 3000 at 2K. We demonstrate the ESR performance of our resonators by measuring donor spin
ensembles in silicon and show that adiabatic pulses can be used to overcome magnetic field inhomogeneities
and microwave power limitations due to the applied bias current. We take advantage of the rapid
tunability of these resonators to manipulate both phosphorus and arsenic spins in a single pulse sequence,
demonstrating pulsed double electron-electron resonance (DEER). Our NbTiN resonator design is useful for
multi-frequency pulsed ESR and should also have applications in experiments where spin ensembles are used as quantum
memories.

During the first year of graduate school, I learned about superconducting qubits and became very interested in them. I wrote up these notes as I read papers in preparation for a class presentation on quantum error correction with superconducting qubits. For simulations, I used Mathematica and its quantum package. [notes] [simulations]